JP3351010B2 - Foil winding transformer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a foil winding transformer used for various electronic devices.

[0002]

2. Description of the Related Art In recent years, transformers have been reduced in cost and size.
In order to meet the market needs for large currents, foil-wound transformers, which have high coupling even with a small number of turns and are structurally suitable for automation, have come to attract attention.

FIG. 6 shows a general structure of a foil wound transformer.

Hereinafter, a conventional foil-wound transformer will be described with reference to FIG. 1 is a cylindrical coil bobbin having a terminal plate portion 1a at one end, 2 is a coil portion formed by winding a metal foil around the coil bobbin 1 via an insulating sheet, 3 is a magnetic core incorporated in the coil bobbin 1, 4 is a lead wire It is.

[0007] Referring to FIG. 6, the coil portion 2 is formed by winding a metal foil having the lead 4 connected to the coil bobbin 1 through an insulating sheet, and the lead 4 is connected to the terminal plate portion 1 a of the coil bobbin 1. And press-fit into the groove 1b on the side surface of the terminal plate portion 1a.
The transformer is completed by incorporating the magnetic core 3.

[0006]

However, in the above-mentioned conventional structure, the lead 4 is connected to the coil bobbin 1.
Since the fulcrum at the time of bending along the corners of the terminal plate portion 1a and the position where the lead 4 is fixed to the terminal plate portion 1a are changed, a displacement or the like of the foil winding occurs and the coil portion is displaced. 2, a large short stress is applied, causing a layer short defect, a winding position defect, a pressure resistance defect, and the like, and a press-fit mistake when the lead 4 is pressed into the groove 1b of the terminal plate portion 1a. Deterioration of quality, deterioration of productivity, and reduction in the operation rate of automatic lines.

Hereinafter, a detailed description will be given with reference to FIGS. 7, 8 and 9. FIG. 7 is a view showing a state of processing of a lead after winding of a conventional foil-wound transformer, FIG. 8 is a view showing a state of processing of a lead after winding of a conventional foil-wound transformer from another angle, and FIG. FIG. 9 is a supplementary explanatory diagram of the lead-out lead in FIG. 8. In FIG. 7, when the lead 4 is shifted from the state (a) to the state (b), that is, the position of the fulcrum A when the lead 4 is bent along the corner of the terminal plate 1a of the coil bobbin 1 and the lead After the lead 4 is shifted from the state (b) to the state (c), that is, the position B when the lead 4 is fixed to the terminal plate portion 1a.
Changes. FIG. 8 shows the movement of the lead 4 from another angle when the lead 4 moves from the point A to the point B. The lead 4 extends from the coil center O to the points A and B. Indicates that the length changes. FIG. 9 shows that the length of the lead 4 is l _{1 when} moving from the point A to the point B in FIG.
From 1 to l ₂ .

Accordingly, in the foil-wound transformer having the conventional structure, the fulcrum when the lead 4 is bent along the corner of the terminal plate 1a of the coil bobbin 1 and the lead 4 are fixed to the terminal plate 1a. Since the position in the state changes, it has been found that the length of the extraction lead 4 changes.

Next, returning to FIG. In FIG. 7, when the position of the lead 4 changes from the state (b) to the state (c), the length of the lead 4 changes according to the above description. Also, at this time, there is no fulcrum to stop the generated stress from being transmitted in the coil direction.
A stress corresponding to the change in the length is applied in the direction of arrow C or the direction of arrow D of the coil portion 2, and a layer short failure, a winding position failure, a pressure resistance failure, or the like may occur. Further, when the stress is not transmitted in the coil direction, the stress is transmitted to the terminal fixing side, which becomes an obstructive stress at the time of terminal press-fitting and fixing. Process quality has deteriorated, which has led to a decrease in productivity and a decrease in the operation rate of automatic lines.

The present invention solves the above-mentioned problems, and when a metal foil is wound and a drawer lead is fixed, a layer short defect, a winding position defect, a breakdown voltage defect, a press fitting error of the drawer lead, and the like are eliminated. The objective is to stabilize the quality, improve the operation rate of the automatic line, automatically produce high-quality foil-wound transformers that can respond to market needs, and provide them at low cost.

[0011]

In order to achieve the above object, a foil-wound transformer according to the present invention comprises a coil bobbin provided with a terminal plate below a cylindrical winding , and one end of a lead .
Connect the coil bobbin via an insulating sheet
A coil portion in which a metal foil is wound around a winding portion of
The drawer leads protrude outward from the front and back of the
The other end of the terminal plate from the lower surface of the terminal plate.
A terminal fixing portion for fixing an intermediate portion of the lead, and the coil
A magnetic core incorporated in a bobbin, and an upper portion of the terminal plate portion
Has a corner at the upper end and the terminal fixing part.
A step portion is formed, and the terminal fixing portion has a front portion.
There is a fixing groove for press-fitting and fixing the drawer lead,
Pull the lead out from the coil to the outside of the fixing groove.
And pull it out in the direction of
Bend in the direction of the upper end of the fixing groove, and follow the step.
And fix the terminal at the upper corner of the step
Between the drawer lead
The part is press-fitted and fixed in the fixing groove .

[0012]

According to the above construction, when the lead is bent and press-fitted into the terminal plate, the step on the side surface of the terminal plate is fixed.
The corner at the upper end of the portion serves as a fulcrum and does not change. Further, since the fulcrum exists at the time of press-fitting, transmission of stress to the coil portion is eliminated. Further, since the disturbance stress change in the length of the outgoing lead of press fitting occurs with respect to the distance from the fulcrum to the terminal fixing portion, it is very small, further deflection that stress out lead at the side of the step portion And it is minimized.

[0013]

(Embodiment 1) An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is an external view of a foil-wound transformer according to a first embodiment of the present invention, FIG. 2 is a view showing a state of processing of lead leads after winding of the foil-wound transformer of the present invention, and FIG. FIG. 4 is a view showing the processing state of the lead-out lead after winding of the foil-wound transformer according to the invention from another angle, and FIG. 4 is a supplementary explanatory view of the lead-out lead in FIG. 1, 2, 3, and 4, reference numeral 10 denotes a cylindrical coil bobbin having a terminal plate portion 11 at the lower end. A plurality of fixing grooves 14 are formed at regular intervals on the side surface of the terminal fixing portion 13 below the portion 12.

The coil bobbin 10 is provided with a coil portion 15 formed by winding a metal foil via an insulating sheet. A plurality of lead leads 16 connected to the metal foil are drawn from the coil portion 15. The coil bobbin 10 incorporates a magnetic core 17 of an EE type or the like to form a foil-wound transformer.

1, the coil portion 15 is formed by winding a metal foil having a lead 16 connected to the coil bobbin 10 through an insulating sheet, and the lead 16 is connected to the terminal plate portion 11 of the coil bobbin 10. After bending along the step portion 12 and press-fitting and fixing the fixing groove 14 of the terminal fixing portion 13 projecting outward, a magnetic core is incorporated to complete the foil winding transformer.

Hereinafter, a detailed description will be given with reference to FIGS. As shown in FIG. 2, when the lead 16 moves from the state (b) to the state (c), that is, it is bent along the step 12 of the terminal plate 11 of the coil bobbin 10 and protrudes outward. The position of the fulcrum E does not change because it is press-fitted and fixed in the fixing groove 14 of the terminal fixing portion 13. Since the fulcrum E is also present when press-fitting and fixing, transmission of stress to the coil side can be stopped. FIG. 3 shows the movement of the lead 16 from a different angle when the lead 16 is fixed to the terminal fixing portion 13.
It does not change up to the point, indicating that the length of the lead 16 from the point E to the point F changes.

FIG. 4 shows a state (c) from the state (b) in FIG.
When moving to the state, the length of the drawer lead 16 is l ₅
Not change, but the stress is not generated, l ₆ indicates that changes to l _7, when the length of the lead-out leads 16 from l ₆ to l ₇ is changed, that the stress is generated slightly Is shown. However, according to the present invention, the stress generated there is actually in a state like the lead-out lead 16 on the upper surface of the step portion 12 in FIG. Therefore, there is almost no practical problem.

As described above, according to the present embodiment, in the foil-wound transformer of the present invention, the step portion 12 is provided on the terminal plate portion 11 of the coil bobbin 10, the corner portion of the step portion 12 is bent, and projected outward. Is fixed to the fixing groove 14 of the terminal fixing portion 13 by press-fitting, so that the fulcrum E at the time of bending the lead 16 along the step portion 12 of the terminal plate portion 11 of the coil bobbin 10 and the terminal fixing portion 13 projecting outward. The position of the fulcrum E at the time of press-fitting into the fixing groove 14 does not change, and the length of the lead 16 from the fulcrum E to the coil center O does not change. Therefore, no stress is generated due to a dimensional change from the point E to the coil center O point.

Also, the lead 16 for terminal press-fitting is used.
The interfering stress caused by the change in the length of the wire will also be reduced, and the generated stress will be alleviated by the bending of the wire,
There is almost no practical problem because it is minimal. In addition, since the fulcrum E is present even when press-fitting is fixed, transmission of stress to the coil side can be completely stopped. Therefore, when winding and fixing the lead 16 to the terminal, the occurrence of a layer short defect, a winding position defect, a withstand voltage defect, a press fitting error of the lead 16 and the like is eliminated.
It is possible to stabilize the process quality and improve the operation rate of the automatic line.

Embodiment 2 Hereinafter, a second embodiment of the present invention will be described with reference to the drawings.

FIG. 5 is a view showing a state of processing of a lead after winding of a foil-wound transformer according to a second embodiment of the present invention. 5 is different from FIG. 2 in that the lead 1 is connected between the step portion 12 and the bottom of the fixing groove 14 of the terminal fixing portion 13.
That is, a step 18 having the same diameter as that of the step 6 is provided.

According to the present embodiment, the stepped portion 18 is provided between the stepped portion 12 and the bottom of the fixing groove 14 of the terminal fixing portion 13 so as to have the same diameter as the lead lead diameter.
5, the lead 16 is more naturally curved, and the relaxation of the stress due to the bending of the wire is minimized, so that the disturbing stress at the time of press-fitting the terminal can be completely eliminated. Therefore, the insertion pressure of the lead 16 can be further reduced, and the production line can be stabilized.

[0024]

As described above, the foil-wound transformer of the present invention is
The top of the terminal board has a corner at the top and a terminal
A stepped part without a fixed part is formed, and the terminal fixed part
Is provided with a fixing groove for press-fitting and fixing the drawer lead.
The lead out from the coil to the outside of the fixing groove.
Direction, and fix the groove with the corner at the upper end of the step as a fulcrum.
Bend in the direction of the upper edge of the
Deflection is provided between the upper corner of the difference part and the terminal fixing part
Since the middle part of the lead is fixed to the fixing groove by press-fitting , (1) when fixing the terminal of the lead, the stress applied to the coil part can be removed, the layer short-circuit defect, the winding position Eliminates the occurrence of defects and breakdown voltage defects.

(2) When the lead-out lead is press-fitted and fixed to the terminal fixing portion, interference stress at the time of press-fitting can be reduced, and occurrence of press-fitting mistake of the lead-out lead can be reduced.

(3) The process quality can be stabilized, and the operation rate of the automatic line can be improved.

In addition, by providing a step portion having the same size as the lead lead diameter between the step portion and the bottom of the terminal fixing portion, (4) the interference stress at the time of press-fitting the terminal of the lead lead is completely reduced. Can be lost.

(5) The insertion pressure of the lead can be further reduced, and the production line can be stabilized.

As described above, a great effect is produced, and a high-quality foil-wound transformer capable of responding to market needs is automatically produced.
It can be provided at low cost.

[Brief description of the drawings]

FIG. 1 is a front view of a foil-wound transformer showing a first embodiment of the present invention.

FIG. 2 is a diagram showing a processing state of a lead after winding of a foil-wound transformer according to the first embodiment of the present invention;

FIG. 3 is a view showing the state of processing of the lead after winding of the foil-wound transformer according to the first embodiment of the present invention, as viewed from another angle.

FIG. 4 is a supplementary explanatory diagram of the drawer lead in FIG. 3;

FIG. 5 is a diagram showing a processing state of a lead after winding of a foil-wound transformer according to a second embodiment of the present invention;

FIG. 6 is a front view of a conventional foil-wound transformer.

FIG. 7 is a view showing a processing state of a lead after winding of a conventional foil-wound transformer.

FIG. 8 is a view showing the processing state of the drawer lead from another angle.

FIG. 9 is an explanatory view of replenishment of the drawer lead.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Coil bobbin 11 Terminal board part 12 Step part 13 Terminal fixing part 14 Fixing groove 15 Coil part 16 Leader lead 17 Magnetic core 18 Step part

──────────────────────────────────────────────────の Continuing from the front page (72) Inventor Tsuneji Imanishi 1006 Kazuma Kadoma, Osaka Pref. Matsushita Electric Industrial Co., Ltd. (72) Kazuhiko Yotsuya 1006 Kazuma Kadoma Kadoma, Osaka Pref. In-company (72) Inventor Shunji Ikeda 1006 Kadoma, Kazuma, Osaka Pref. Matsushita Electric Industrial Co., Ltd. (56) References JP-U 4-94709 (JP, U) JP-U 4-130418 (JP, U) (58) Fields surveyed (Int. Cl. ⁷ , DB name) H01F 27/28 H01F 30/00

Claims (2)

(57) [Claims] 1. A connection between a coil bobbin provided with a terminal plate portion below a cylindrical winding portion and one end of a lead-out lead.
The metal is wound on the winding part of the coil bobbin via an insulating sheet.
A coil portion wound with a metal foil, a front surface of the terminal plate portion and
Protrude outward on the back and connect the other end of the drawer lead to the
Protrude from the lower surface of the terminal plate and
And a terminal fixing part having a fixed part and the coil bobbin.
With a magnetic core inserted therein, and an upper end on the upper end of the terminal plate portion.
Stepped portion having a corner portion and not having the terminal fixing portion
The terminal fixing portion is provided with the drawer
A fixing groove for press-fitting the card is provided.
Pull the lead from the coil part in the direction outward of the fixing groove.
The fixing groove with the corner at the upper end of the step as a fulcrum.
Bend in the direction of the upper end of the
Between the corner at the upper end of the step portion and the terminal fixing portion.
Provide a bend and fix the middle part of the drawer lead
A foil-wound transformer press-fitted into the groove . 2. The foil-wound transformer according to claim 1, wherein a step of the same size as the diameter of the lead is provided between the step and the bottom of the fixing groove of the terminal fixing section.